120 



FOREST RENEWAL 



LEONARD I. BARRETT 



Forestry attempts to perpetuate at 

 the least cost the species that will pro- 

 vide the greatest volume of useful 

 commodities. In forestry, harvesting is 

 followed promptly by a new crop, and 

 maximum productivity is maintained 

 in perpetuity. 



The means of establishing new for- 

 est crops are few. They include plant- 

 ing small trees or seed, securing a 

 growth of sprouts, and natural seeding 

 from the mature forest. The first two 

 are important locally in several of the 

 forest regions of the United States, but 

 prompt forest renewal, through repro- 

 duction by natural seeding, is appli- 

 cable wherever standing forests exist. 



My purpose here is to discuss the 

 basic factors that must be considered 

 in seeking natural forest renewal and 

 the methods that are finding success in 

 the United States. 



The methods of renewing forests 

 were born at least 700 years ago, when 

 the feudal lords and communal forest 

 owners of central Europe felt the pinch 

 of short wood supplies and vanishing 

 game habitats and, through edicts and 

 restrictions, sought to perpetuate for- 

 est resources. At first, the methods 

 were based on the observations and 

 folklore of huntsmen and did not begin 

 to receive the benefit of systematic and 

 scientific scrutiny until about the mid- 

 dle of the eighteenth century. From 

 then on, progress was comparatively 

 fast; within 100 years European forest- 

 ers developed well-defined and effec- 

 tive ways to get continued productivity 

 of forests. The practice of forestry was 

 elevated from a folklore or speculative 

 status to that of applied science. 



The beginning of a conservation 

 movement in the United States about 

 50 years ago saw many attempts in 

 teaching, research, and practice to 

 transplant the European prescriptions 

 to American forests. They did not suc- 

 ceed too well. Gradually, as our own 



basic knowledge expands, methods 

 more applicable to our varied forests 

 and their requirements are emerging 

 and creating an American science 

 of silviculture. The science is still in 

 its infancy, and many more years of 

 experience and research will be needed 

 before sound solutions are obtained to 

 many important problems of forest re- 

 newal. But American foresters believe 

 that modern methods of research will 

 shorten this period of development. 



If a farmer, in one operation, could 

 harvest this year's crop of grain and 

 sow the next, using a fraction of the 

 crop as seed, he would accomplish an 

 operation similar to the one the forest 

 grower uses in renewing a timber crop. 

 For farm crops it would not work, be- 

 cause the life processes of the plants 

 require intense culture and care if the 

 yield is to be worth while. The farm 

 manager approaches his job with the 

 viewpoint of comparatively complete 

 control of the crop environment that 

 is needed to meet the demanding re- 

 quirements of specific plants. He has 

 learned that it pays to modify the 

 weather; he controls moisture by irri- 

 gation and frost by smudge pots. 



Trees also are demanding in their 

 requirements for germination, early 

 survival, and best growth. The cul- 

 tural measures necessary to meet these 

 requirements, however, are generally 

 quite different from those needed to 

 meet the requirements of farm crops. 

 The intensity of culture used in farm- 

 ing would be wasteful and sometimes 

 inimical to successful forest renewal. 

 Another article in this book discusses 

 the biology of the forest, and shows 

 how natural trends over long periods 

 change the species in a forest. It indi- 

 cates also that forests respond to the 

 natural variations in the factors that 

 affect tree growth by a change in spe- 

 cies or in rate of growth and thrift. 



The biological basis of successful 



